Surface cleaning apparatus, and a charging unit therefor

ABSTRACT

A surface cleaning apparatus, such as a portable surface cleaning apparatus is powered by one or more ultracapacitors and a charging unit for same is provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/281,788, filed on Feb. 21, 2019, now allowed, the content of which isincorporated herein in its entirety by reference.

FIELD

This disclosure relates generally to appliances, such as a surfacecleaning apparatus, that are operable in a cordless mode. Thisdisclosure also relates to charging units for energy storage membersused in portable appliances, such as a surface cleaning apparatus, andin particular charging units with an on board energy storage member.

INTRODUCTION

The following is not an admission that anything discussed below is partof the prior art or part of the common general knowledge of a personskilled in the art.

U.S. Pat. No. 8,183,819 B2 of Sugano purports to disclose aboosting-charge power supply apparatus which supplies electric power forcharging a mobile body having a boosting-charge control function, whichincludes: a rectifier for supplying DC power; a first power storage forstoring DC power from the rectifier and outputting DC power; a chargingcircuit which sends DC power from the first power storage directly to avehicle including a second power storage for storing DC power from thefirst power storage; and a power-supply controller for stopping therectifier from supplying electric power to the first power storage whilethe first power storage is supplying electric power to charge the secondpower storage. Through the controller, DC power supplied from the firstpower storage becomes suitable for charging of the second power storageon the vehicle side, thereby enabling the same boosting-charge powersupply apparatus to supply electric power and give a boosting charge toa different type of vehicle.

U.S. Pat. No. 8,482,263 B2 of Barrade et al. purports to disclose amethod for rapidly charging a rechargeable device. An embodiment of themethod comprises charging a first supercapacitor attached to a chargingunit. In response to the device coupling to the charging unit,determining whether the charging unit is authorized to charge thedevice. The first supercapacitor discharging in response to thedetermining that the charging unit is authorized to charge the device,the discharging of the first supercapacitor resulting in a first currentbeing generated. The first current is transferred to the device throughan output of the charging unit for charging a second supercapacitorincluded in the device. The amount of the first current generated isregulated in response to the voltage at the output increasing at a rateabove a set threshold, reducing the rate at which the voltage isincreasing.

Unites States Publication No. 2016/0285289 A1 of Arends purports todisclose a battery charger with an internal power storage device thatmay be used to facilitate fast charging of a battery by using a highC-rate. A battery charger with an internal power storage device mayinclude a control circuit that receives operating mode instructions tooperate in a base charging mode or a fast charging mode. In the basecharging mode, the battery charger may be configured to concurrentlycharge a battery and an internal power storage device at a base C-rateusing current supplied from an external power source. In the fastcharging mode, the battery charger may be configured to charge thebattery at a high C-rate, which is substantially higher than the baseC-rate, by using the internal power storage device. The battery chargermay include an optical reader used to identify battery-specificcharacteristics and enable the fast charging mode.

SUMMARY

The following introduction is provided to introduce the reader to themore detailed discussion to follow. The introduction is not intended tolimit or define any claimed or as yet unclaimed invention. One or moreinventions may reside in any combination or sub-combination of theelements or process steps disclosed in any part of this documentincluding its claims and figures.

In accordance with an aspect of this disclosure, which may be used aloneor in combination with any other aspect, it may be desirable for anenergy storage member that powers a portable appliance, such as a handvacuum cleaner, to be charged rapidly. This may reduce the downtime of,e.g., a hand vacuum cleaner that is powered by the energy storagemember. This may also allow the e.g., a hand vacuum cleaner to have lesson board stored power, which may be achieved by, e.g., using energystorage members that have a lower storage capacity and/or using fewertotal energy storage members. As a result, the overall weight of theappliance may be reduced.

Ultracapacitors can be rapidly charged and discharged. Ultra-capacitorsalso tend to tolerate a greater number of charge and discharge cycles ascompared to conventional rechargeable batteries. Using ultracapacitorsas the energy supply for portable power appliances allows thoseappliances to be rapidly charged to an active state. However,ultra-capacitors may have a lower power storage capacity as compared toconventional rechargeable batteries.

To enable a portable appliance that utilizes ultracapacitors, it wouldbe beneficial to provide a nearby power source that is able to rechargethe ultra-capacitor rapidly, and in some cases multiple times withoutbeing depleted. However, portable power appliances supply such asoutdoor lawn and garden tools are often used distant from a mains powersupply. Also, a hand vacuum cleaner may be used in a room that is distalto a docking station. In such cases, it would be desirable to be able tocharge the power appliance even when a mains power supply is not locatednearby. Incorporating an onboard energy storage member into a portablecharging unit may facilitate rapid recharges of the ultracapacitors,even when removed from a mains power supply.

In accordance with this broad aspect, there is provided a portablecharging unit electrically connectable to a mains power supply, theportable charging unit comprising:

-   -   (a) a hand carriable battery charger body;    -   (b) an onboard energy storage member; and,    -   (c) a power output circuit, which in operation, is electrically        connected to the onboard energy storage member,    -   wherein an ultracapacitor for a portable power appliance is        electrically connectable to the portable charging unit, and    -   in an onboard energy storage member charging mode, the portable        charging unit is electrically connected to the mains power        supply, and the portable charging unit is operable to charge the        onboard energy storage member using power from the mains power        supply; and,    -   in an ultracapacitor charging mode, the onboard energy storage        member is electrically connected to the power output circuit and        the ultracapacitor is also electrically connected to the power        output circuit, whereby the portable charging unit is operable        to charge the ultracapacitor by discharging stored energy from        the energy storage member.

In some embodiments, the onboard energy storage member may comprise alead acid battery.

In some embodiments, the power output circuit may omit any overvoltageprotection circuitry.

In some embodiments, the charging unit may further comprise an outputdisplay operable to display a charge state of the onboard energy storagemember.

In some embodiments, the charging unit may further comprise an outputdisplay operable to display a charge state of the ultracapacitor whenthe ultracapacitor is electrically connected to the power outputcircuit.

In some embodiments, in the ultracapacitor charging mode, theultracapacitor may be recharged at a rate of at least 4 C. In someembodiments, in the ultracapacitor charging mode, the ultracapacitor maybe recharged at a rate of at least 6 C.

In some embodiments, the charging unit may further comprise a thermalcooling unit wherein, in the onboard energy storage member chargingmode, the thermal cooling unit is thermally connected to the energystorage member. In some embodiments, in the onboard energy storagemember charging mode, the thermal cooling unit may be directly thermallyconnected to the energy storage member. Optionally, in such anembodiment, the ultracapacitor charging mode, the ultracapacitor may berecharged at a rate of at least 4 C.

In some embodiments, the charging unit may further comprise a thermalcooling unit; wherein in the ultracapacitor charging mode, the thermalcooling unit is thermally connected to the ultracapacitor. Optionally,in such an embodiment, in the ultracapacitor charging mode, theultracapacitor is recharged at a rate of at least 4 C. In someembodiments, in the ultracapacitor charging mode, the ultracapacitor isrecharged at a rate of at least 6 C.

In some embodiments, the charging unit may further comprise anelectrical cord removably connectable with the mains power supply.

In some embodiments, the portable power appliance may comprise one of apower tool, a landscaping tool, a vacuum cleaner, and a kitchenappliance.

In some cases, it may also be desirable to charge the appliance energystorage member rapidly without overheating the energy storage member.This is the case whether the charging unit is portable and/or thecharging of an energy storage member occurs while the energy storagemember is located in a portable appliance. However, incorporatingcooling components into a portable charger or a portable applianceincreases the weight of the charger/appliance, which may be cumbersome,e.g., in portable appliances that are carried by users. However, if anenergy storage member may be rapidly charged, then a shorter run timefor an appliance may be acceptable by a user. Accordingly, fewer energystorage members may be provided. According, providing a portable chargerwhich includes a cooling member may facilitate a portable appliancehaving a lower on board energy storage capacity.

In the case of a portable appliance having an on board charger, usingfewer energy storage members may offset some or all of the weight of acooling unit. Accordingly, a thermal cooling unit may be incorporatedinto the charging unit of a portable appliance. The thermal cooling unitcan absorb thermal energy that is generated when the appliance energystorage member is charged, and then dissipate this thermal energy whilethe appliance is being used. Accordingly, the portable appliance maycontain energy storage members that provide, e.g., up to a 5, 6, 7, 8,9, 10 or 15 minute run time at full power. This may reduce a the weightof a heavy component of the portable appliance thereby permitting athermal cooling unit to be provided.

In accordance with this broad aspect, there is provided a portablecharging unit electrically connectable to a mains power supply, theportable charging unit comprising:

-   -   (a) a hand carriable battery charger body;    -   (b) an onboard energy storage member;    -   (c) a power output circuit, which in operation is electrically        connected to the onboard energy storage member; and,    -   (d) a thermal cooling unit. which in operation is thermally        connected to at least one of the onboard energy storage member        and an appliance energy storage member for a portable power        appliance,    -   wherein the appliance energy storage member is electrically        connectable to the portable charging unit and,    -   in an onboard energy storage member charging mode, the portable        charging unit is electrically connected to the mains power        supply and, the battery charger is operable to charge the        onboard energy storage member using power from the mains power        supply; and    -   in an appliance energy storage member charging mode, the onboard        energy storage member is electrically connected to the power        output circuit and the appliance energy storage member is also        electrically connected to the power output circuit, whereby the        charging unit is operable to charge the appliance energy storage        member by discharging stored energy from the onboard energy        storage member to the appliance energy storage member.

In some embodiments, the onboard energy storage member comprises a leadacid battery.

In some embodiments, the appliance energy storage member may comprise alithium ion battery.

In some embodiments, the appliance energy storage member may comprise anultracapacitor.

In some embodiments, in the appliance energy storage member chargingmode, the thermal cooling unit may be thermally connected to theappliance energy storage member.

In some embodiments, in an appliance energy storage member chargingmode, the appliance energy storage member may be recharged at a rate ofat least 4 C.

In accordance with this broad aspect, there is also provided a kitcomprising:

-   -   (a) a portable power appliance comprising a motor and an        appliance energy storage member electrically connectable to the        motor;    -   (b) a hand carriable battery charger electrically connectable to        a mains power supply, the hand carriable battery charger        comprising: an onboard energy storage member electrically        connectable to the battery charger; and, a power output circuit        having an appliance electrical port that is electrically        connectable to the appliance energy storage member,    -   wherein    -   in an onboard energy storage member charging mode, the battery        charger is electrically connected to the mains power supply, the        battery charger is operable to charge the onboard energy storage        member using power from the mains power supply; and,    -   when in the appliance energy storage charging mode, the        appliance energy storage member is electrically connected to the        appliance electrical port and the appliance energy storage        member is also electrically connected to the power output        circuit, whereby the charging unit is operable to charge the        appliance energy storage member by discharging stored energy        from the onboard energy storage member to the appliance energy        storage member.

In some embodiments, the onboard energy storage member may comprise alead acid battery.

In some embodiments, the appliance energy storage member may comprise alithium ion battery.

In some embodiments, the appliance energy storage member may comprise anultracapacitor.

In some embodiments, in the appliance energy storage charging mode, theappliance energy storage member may be recharged at a rate of at least 4C. In some embodiments, in the appliance energy storage charging mode,the appliance energy storage member may be recharged at a rate of atleast 6 C.

In some embodiments, the portable power appliance may comprise anappliance electrical cord having a first end that is electricallyconnectable to the appliance energy storage member and a second end;and, the appliance electrical port defines an appliance power outletthat is electrically connectable to the second end of the applianceelectrical cord, whereby when the onboard energy storage member iselectrically connected to the battery charger and the appliance energystorage member is electrically connected to the appliance electricalport, power from the onboard energy storage member is provided to theappliance energy storage member via the appliance electrical cord.

In some embodiments, the portable power appliance may comprise a mainbody; the motor is provided within the main body; the appliance energystorage member is removable from the main body; and, the applianceenergy storage member is directly mountable to the appliance electricalport.

In some embodiments, the portable power appliance may comprise one of apower tool, a landscaping tool, a surface cleaning apparatus such as avacuum cleaner, and a kitchen appliance.

In accordance with an aspect of this disclosure, which may be used aloneor in combination with any other aspect, it may be desirable to preventan energy storage member from being overcharged. Allowing the energystorage member to be overcharged can result in damage and degradation ofthe energy storage member, thereby reducing the usable lifespan of theenergy storage member. Accordingly, a charging unit may be adapted toprevent the energy storage member that is being charged from reaching anovervoltage condition.

While active feedback and monitoring systems may be used to preventovercharging of energy storage members, active feedback components thatmonitor the charge state of an energy storage member increase the sizeand cost of the charging unit. Accordingly, a charging unit that isconfigured to prevent an overcharge state through the configuration ofthe power output circuit, such as omiting any overvoltage protectioncircuitry, may protect the energy storage member while reducing size,complexity and manufacturing costs.

In accordance with this broad aspect, there is provided a charging unitelectrically connectable to a mains power supply, the charging unitcomprising:

-   -   (a) a battery charger body;    -   (b) an onboard energy storage member having a positive electrode        and a negative electrode; and,    -   (c) a power output circuit which omits any overvoltage        protection circuitry and which, in a charging mode, is        electrically connected to the onboard energy storage member,    -   wherein an ultracapacitor for a portable power appliance is        electrically connectable to the portable charging unit, and    -   when the ultracapacitor is electrically connected to the power        output circuit, the ultracapacitor is connected between the        positive electrode and the negative electrode of the onboard        energy storage member in an open circuit charging configuration        whereby a maximum charge state of the ultracapacitor is defined        by a voltage level of the onboard energy storage member.

In some embodiments, the power output circuit may comprise a loadresistor, and when the ultracapacitor is connected to the power outputcircuit, the load resistor is in series with the ultracapacitor betweenthe positive electrode and the negative electrode.

In some embodiments, the power output circuit may comprise a loadinductor, and when the ultracapacitor is connected to the power outputcircuit, the load inductor is in series with the ultracapacitor betweenthe positive electrode and the negative electrode.

In some embodiments, the charging unit may be hand carriable.

In some embodiments, the charging unit may further comprise anelectrical cord removably connectable with the mains power supply.

In some embodiments, the energy storage member may comprise a lead acidbattery.

In some embodiments, the energy storage member may comprise a lithiumion battery.

In some embodiments, the charging unit may further comprise an outputdisplay operable to display a charge state of the ultracapacitor whenthe ultracapacitor is electrically connected to the power outputcircuit.

In some embodiments, the charging unit may further comprise a controlcircuit operable to determine the charge state of the ultracapacitor bymeasuring a current flow level through the power output circuit when theultracapacitor is electrically connected to the power output circuit.

In some embodiments, the charging unit may further comprise an outputdisplay operable to display a charge state of the energy storage member.

In some embodiments, when the ultracapacitor is electrically connectedto the power output circuit, the ultracapacitor may be recharged at arate of at least 4 C.

In some embodiments, when the ultracapacitor is electrically connectedto the power output circuit, the ultracapacitor may be recharged at arate of at least 6 C.

In some embodiments, the portable power appliance comprises one of apower tool, a landscaping tool, a surface cleaning apparatus such as avacuum cleaner, and a kitchen appliance.

In some embodiments, the ultracapacitor is directly connectable with thepower output circuit.

When the energy storage member being charged is an ultracapacitor, itmay be desirable to reduce the level of inrush current that may arisewhen a depleted ultracapacitor is initially connected to the chargingunit. A depleted ultracapacitor may operate essentially as a shortcircuit resulting in a high current level for a constant voltage source.Accordingly, in accordance with an aspect of this disclosure, which maybe used alone or in combination with any other aspect, incorporating aload component such as a resistive or inductive load component in linewith the ultracapacitor may prevent the inrush current from damagingcomponents of the charging unit or overheating the charging unit.

In accordance with this aspect of the disclosure, there is also provideda charging unit electrically connectable to a mains power supply, thecharging unit comprising:

-   -   (a) a battery charger body;    -   (b) an onboard energy storage member electrically having a        positive electrode and a negative electrode; and    -   (c) a power output circuit comprising an electrical output port        that is electrically connectable to an ultracapacitor and an        output circuit load in series with the electrical output port,    -   wherein    -   when the ultracapacitor is electrically connected to the        electrical output port, the ultracapacitor is connected to the        energy storage member in an open circuit charging configuration        whereby a maximum charge state of the ultracapacitor is defined        by a voltage level of the onboard energy storage member; and    -   when the ultracapacitor is electrically connected to the        electrical output port, the ultracapacitor is connected in        series with the load component between the positive electrode        and the negative electrode whereby an inrush current from the        onboard energy storage member to the ultracapacitor is reduced        by the load component.

In some embodiments, the output circuit load may comprise one of a loadinductor and a load resistor.

In some embodiments, the energy storage member may comprise a lead acidbattery.

In some embodiments, the charging unit may further comprise a controlcircuit operable to determine the charge state of the ultracapacitor bymeasuring a current flow level through the power output circuit when theultracapacitor is electrically connected to the electrical output port.

In some embodiments, the charging unit may further comprise an outputdisplay operable to display a charge state of the energy storage member.

In some embodiments, when the ultracapacitor is electrically connectedto the power output circuit, the ultracapacitor may be recharged at arate of at least 4 C.

In some embodiments, the ultracapacitor may be directly connectable withthe electrical output port.

In some embodiments, the power output circuit may omit any overvoltageprotection circuitry.

In accordance with an aspect of this disclosure, which may be used aloneor in combination with any other aspect, it may be desirable for anappliance charging unit to be capable of powering a portable powerappliance directly, as well as charging the appliance energy storagemember. This may allow the charging unit to operate as a mobile powersupply for the portable power appliance that has greater capacity thanthe appliance energy storage members. This may also allow the appliancecharging unit to extend the operational period of the portable powerappliance beyond what may be provided if the appliance operates only offpower from an integrated appliance energy storage member.

In accordance with this broad aspect, there is provided an appliancecharging unit electrically connectable to a mains power supply, theappliance charging body comprising:

-   -   (a) a battery charger body;    -   (b) an onboard energy storage member; and,    -   (c) a power output circuit electrically connectable to a        portable power appliance that includes a motor and an appliance        energy storage member,    -   wherein    -   when the portable power appliance is connected to the power        output circuit, the charging unit is operable in a first mode of        operation and a second mode of operation;    -   in the first mode of operation the charging unit is operable to        power the motor directly using power from the onboard energy        storage member; and    -   in the second mode of operation, the charging unit is operable        to charge the appliance energy storage member using power from        the onboard energy storage member.

In some embodiments, the onboard energy storage member may comprise alead acid battery.

In some embodiments, the onboard energy storage member may comprise alithium ion battery.

In some embodiments, the appliance energy storage member may comprise anultracapacitor.

In some embodiments, in the first mode of operation, the charging unitmay be operable to charge the appliance energy storage member also whilepowering the motor.

In some embodiments, when the appliance charging unit is electricallyconnected to the mains power supply, the charging unit may be operablein a third mode of operation in which power from the mains power supplyis used to power the portable power appliance.

In some embodiments, the charging unit may be operable in the first modeof operation when the appliance charging unit is disconnected from themains power supply.

In some embodiments, the charging unit may be operable in the secondmode of operation when the battery charger is disconnected from themains power supply.

In some embodiments, the charging unit may be hand carriable.

In some embodiments, the power output circuit may include a first poweroutput port and a second power output port; the first power output portmay be electrically connectable to the portable power appliance; thesecond power output port may be electrically connectable to the portablepower appliance; wherein, when the portable power appliance iselectrically connected to the first power output port, the charging unitis configured to operate in the first mode of operation; and wherein,when the portable power appliance is electrically connected to thesecond power output port, the charging unit is configured to operate inthe second mode of operation.

In some embodiments, the portable power appliance may include anappliance electrical cord, and the first power output port and thesecond power output port are separately connectable with the applianceelectrical cord.

In some embodiments, the power output circuit may include a storagemember power output port, and the appliance energy storage member isdirectly engageable with the storage member power output port.

In some embodiments, the appliance charging unit may further comprise acharger electrical cord removably connectable with the mains powersupply.

In some embodiments, the charging unit may include a retractable cordreel, and the charger electrical cord is connected to the retractablecord reel.

In some embodiments, the portable power appliance may comprise one of apower tool, a landscaping tool, a vacuum cleaner, and a kitchenappliance.

In some embodiments, the portable power appliance may comprise anappliance main body, and the charging unit is mountable to the appliancemain body.

It will be appreciated by a person skilled in the art that an apparatusor method disclosed herein may embody any one or more of the featurescontained herein and that the features may be used in any particularcombination or sub-combination.

These and other aspects and features of various embodiments will bedescribed in greater detail below.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the described embodiments and to show moreclearly how they may be carried into effect, reference will now be made,by way of example, to the accompanying drawings in which:

FIG. 1 is a perspective view of an example portable power appliance inaccordance with an embodiment;

FIG. 2 is an exploded view of the components of a portable powerappliance of FIG. 1;

FIG. 3 is a perspective view of a removable portion of the portablepower appliance of FIG. 2;

FIG. 4 is a side elevation view of the removable portion of the portablepower appliance of FIG. 3 with an energy storage member removed;

FIG. 5 is a perspective view of the energy storage member of FIG. 4 andan example charging unit in accordance with an embodiment;

FIG. 6 is a schematic illustration of a portable power appliance andcharging unit in accordance with an embodiment;

FIG. 7 is a schematic illustration of an example charging unit inaccordance with an embodiment;

FIGS. 8A-8D are schematic illustrations of example power output circuitsfor the charging unit of FIG. 7;

FIG. 9 is a schematic illustration of another example charging unit inaccordance with an embodiment;

FIG. 10A is a schematic illustration of another example charging unit inaccordance with an embodiment;

FIG. 10B is a schematic illustration of another example charging unit inaccordance with an embodiment;

FIGS. 11-15 are schematic illustrations of an energy storage member, athermal cooling unit, and a charger circuit, in accordance with variousembodiments;

FIG. 16 is a schematic illustration of a portable power appliance inaccordance with an embodiment;

FIG. 17 is a perspective view of the portable power appliance of FIG. 15connected by a power cable to a stationary power supply, in accordancewith an embodiment; and,

FIG. 18 is a schematic illustration of another example portable powerappliance in accordance with an embodiment;

The drawings included herewith are for illustrating various examples ofarticles, methods, and apparatuses of the teaching of the presentspecification and are not intended to limit the scope of what is taughtin any way.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Various apparatuses, methods and compositions are described below toprovide an example of an embodiment of each claimed invention. Noembodiment described below limits any claimed invention and any claimedinvention may cover apparatuses and methods that differ from thosedescribed below. The claimed inventions are not limited to apparatuses,methods and compositions having all of the features of any oneapparatus, method or composition described below or to features commonto multiple or all of the apparatuses, methods or compositions describedbelow. It is possible that an apparatus, method or composition describedbelow is not an embodiment of any claimed invention. Any inventiondisclosed in an apparatus, method or composition described below that isnot claimed in this document may be the subject matter of anotherprotective instrument, for example, a continuing patent application, andthe applicant(s), inventor(s) and/or owner(s) do not intend to abandon,disclaim, or dedicate to the public any such invention by its disclosurein this document.

The terms “an embodiment,” “embodiment,” “embodiments,” “theembodiment,” “the embodiments,” “one or more embodiments,” “someembodiments,” and “one embodiment” mean “one or more (but not all)embodiments of the present invention(s),” unless expressly specifiedotherwise.

The terms “including,” “comprising” and variations thereof mean“including but not limited to,” unless expressly specified otherwise. Alisting of items does not imply that any or all of the items aremutually exclusive, unless expressly specified otherwise. The terms “a,”“an” and “the” mean “one or more,” unless expressly specified otherwise.

As used herein and in the claims, two or more parts are said to be“coupled”, “connected”, “attached”, or “fastened” where the parts arejoined or operate together either directly or indirectly (i.e., throughone or more intermediate parts), so long as a link occurs. As usedherein and in the claims, two or more parts are said to be “directlycoupled”, “directly connected”, “directly attached”, or “directlyfastened” where the parts are connected in physical contact with eachother. None of the terms “coupled”, “connected”, “attached”, and“fastened” distinguish the manner in which two or more parts are joinedtogether.

Furthermore, it will be appreciated that for simplicity and clarity ofillustration, where considered appropriate, reference numerals may berepeated among the figures to indicate corresponding or analogouselements. In addition, numerous specific details are set forth in orderto provide a thorough understanding of the example embodiments describedherein. However, it will be understood by those of ordinary skill in theart that the example embodiments described herein may be practicedwithout these specific details. In other instances, well-known methods,procedures, and components have not been described in detail so as notto obscure the example embodiments described herein. Also, thedescription is not to be considered as limiting the scope of the exampleembodiments described herein.

General Description of a Portable Power Appliance

Referring to FIGS. 1-6, exemplary embodiments of a portable powerappliance are shown generally as 100. The following is a generaldiscussion of apparatus 100 which provides a basis for understandingseveral of the features which are discussed herein. As discussedsubsequently, each of the features may be used individually or in anyparticular combination or sub-combination in this or in otherembodiments disclosed herein.

In the example of FIG. 1, the portable power appliance 100 is a surfacecleaning apparatus. Although portable power appliance 100 is shown as asurface cleaning apparatus, it should be understood that other portablepower appliances such as power tools (e.g. drills, screwdrivers, powersaws), landscaping tools (e.g. lawn mowers, weed whackers, hedgetrimmers, leaf blowers, snow removal equipment such as snow blowers),and kitchen appliances (e.g., a hand mixer) may be used in embodimentsdescribed herein.

Surface cleaning apparatus 100 may be any type of surface cleaningapparatus, including for example a stick vacuum cleaner as exemplifiedin FIG. 1, an upright vacuum cleaner, a canister vacuum cleaner, anextractor or a wet/dry type vacuum cleaner. Optionally, the surfacecleaning apparatus 100 may use one or more cyclones and may therefore bea cyclonic surface cleaning apparatus.

Portable power appliance 100 is an example of a power appliance having abase section and a removable portion mounted to the base section. InFIGS. 1-6, surface cleaning apparatus 100 is illustrated as including afloor cleaning unit 104 as the base section, and a portable surfacecleaning unit 108 (which may be referred to as a hand vacuum cleaner)that is removably connectable to the floor cleaning unit 104. Otherexamples of portable power appliances having removable portions mayinclude stand mixers with removable hand mixers, or surface cleaningapparatuses having lift away modules or canisters. An example is anupright vacuum cleaner with a lift away module, such as is shown in USpatent publication No. 2014/0237755.

In the example of appliance 100, floor cleaning unit 104 may include asurface cleaning head 112 adapted to clean floors. Portable surfacecleaning unit 108 may include an air treatment member 116. Surfacecleaning apparatus 100 may include an upright configuration (alsoreferred to as a ‘floor cleaning configuration’, see FIG. 1) in whichportable surface cleaning unit 108 is mounted to floor cleaning unit104, and dirty air that enters at surface cleaning head 112 flowsdownstream to portable surface cleaning unit 108 where the dirty air iscleaned by air treatment member 116. Surface cleaning apparatus 100 mayalso include a ‘portable cleaning configuration’ (also referred to as a‘hand carriable configuration’, or ‘above-floor cleaning configuration’,see FIGS. 3 and 4), in which portable surface cleaning unit 108 isseparated from floor cleaning unit 104, such as to clean above-floorsurfaces and surfaces generally inaccessible to or unsuitable forcleaning with surface cleaning head 112 for example. In any suchconfiguration, a user may manipulate the appliance 100 using handle 120.

In general, portable power appliances described in the embodimentsherein include one or more electrical components such as a motor,control unit, and/or output display. For instance as shown in FIG. 4,portable surface cleaning unit 108 may include a suction motor 212 togenerate vacuum suction through the air flow path of the surfacecleaning apparatus 100. Various other types of electrical motors oractuators may be used depending on the type of appliance. In the exampleshown, suction motor 212 may be a fan-motor assembly including anelectric motor and impeller blade(s).

A trend in some portable power appliances such as cordless vacuumcleaners is to provide longer runtime in a single charge. For example,some cordless vacuum cleaners can run continuously for 30 minutes ormore before recharging. However, such vacuum cleaners require multiplelarge, expensive, heavy batteries. In use, this can make these vacuumcleaners unwieldy to carry, in both size and weight. Moreover, it cantake a long time to fully recharge a plurality of high capacitybatteries, and batteries often degrade and require replacement duringthe working life of a vacuum cleaner. The battery replacement cost is asignificant expense for the user.

In some embodiments disclosed herein, a portable power appliance may beequipped with an energy storage member comprising or consisting of oneor more capacitors. As compared with rechargeable batteries (e.g.lead-acid, Ni-Cad, NiMH, or lithium), a capacitor can be recharged muchfaster, and have a much longer lifespan (measured in charge cycles).With battery powered appliances, traditional design philosophy is thatit is important to have a long runtime to mitigate having to recharge inthe middle of a cleaning session, since the recharge could take severalhours, which would be disruptive to the user who wishes to finish theircleaning session in a timely manner.

In contrast, with a capacitor powered portable appliance, the need torecharge mid-session may be minimally disruptive as it may only requirea few seconds to a few minutes to recharge. Therefore, a capacitorpowered portable appliance may include comparatively less energy storagecapacity because avoiding a recharge mid-session is not a priority. As aresult, a capacitor powered portable appliance may have one or morecapacitor that are relatively smaller and lighter as compared with ahigh capacity battery. This can make a capacitor powered portableappliance unit smaller and lighter overall, without compromisingperformance (e.g., air flow rate and/or suction power) or userexperience. Moreover, the long lifespan of capacitors (often 1 millioncharge cycles or more) means that the capacitors will not generallyrequire replacement during the working life of the portable appliance.

For convenience, reference to “a capacitor” herein means “one or morecapacitors”, unless expressly stated otherwise (e.g. “a singlecapacitor”). Similarly, reference to “a battery” herein means “one ormore batteries”, unless expressly stated otherwise (e.g. “a singlebattery”).

Referring to FIGS. 4 and 6, the portable surface cleaning unit 108 ofappliance 100 is shown including an energy storage member 272. Energystorage member 272 may comprise or consist of a capacitor 276. Forexample, capacitor 276 may be the only significant energy storage inenergy storage member 272, or energy storage member 272 may furtherinclude a battery. Some or all of the power consuming elements ofappliance 100 may be powered by capacitor 276. For example, at leastsuction motor 212 may be powered by capacitor 276. In some embodiments,some or all power consuming elements of portable surface cleaning unit108 may be exclusively powered by capacitor 276. For example, at leastsuction motor 212 may be exclusively powered by capacitor 276 in someembodiments.

In some embodiments, the appliance energy storage member 272 included inthe removable section 108 may include all of the energy storage membersfor the entire appliance. Additionally or alternatively, the basesection 104, which may include a brush motor, may include one or moreappliance energy storage members 272.

Capacitor 276 may be any capacitor suitable for supplying power requiredto operate at least suction motor 212. For example, capacitor 276 may bean ultracapacitor (also referred to as a supercapacitor or Goldcap™). Ascompared to an electrolytic capacitor, ultracapacitors have dramaticallyhigher energy density (per unit mass and per unit volume). Types ofultracapacitors include electrostatic double-layer capacitors (EDLCs),electrochemical pseudocapacitors, and hybrid capacitors that storecharge both electrostatically and electrochemically. Capacitor 276 maybe recharged by power from a power source external to portable surfacecleaning unit 108.

As shown in FIGS. 1-4, the portable power appliance 100 may have a mainbody 180. The motor 212 can be contained within the main body 180 of theappliance 100. The appliance energy storage member 272 can also bemounted to, or within the main body 180. In some embodiments, theappliance energy storage member 272 may be removable from the main body180 for charging.

FIGS. 4-5 show an example in which energy storage member 272 isremovable from portable surface cleaning unit 108 for electricallyconnecting to an external charging unit 280. The energy storage member272 may be maintained within an energy storage member housing 273. Theappliance energy storage member 272 may be removed from the appliance100 while within this housing 273. Alternately, only the energy storagemember 272 may be removable or a housing 273 may be removable and theenergy storage member 272 may then be removed from housing 273 forcharging.

External charging unit 280 may be powered by an electrical connection toa stationary power supply 284 (e.g. mains power). An advantage of thisdesign is that it can allow the user to swap a discharged energy storagemember 272 for a charged energy storage member 272, which may be storedon the charging unit 280. The external charging unit 280 also reducesthe size and weight of portable power appliance 100 as compared withincluding the charging unit 280 within portable power appliance 100.Further, this design may not require portable appliance 100 to have apower cord or power cord connector, which may also reduce the size andweight of appliance 100 all else being equal.

Alternatively or in addition to energy storage member 272 beingremovable for recharging, energy storage member 272 may be rechargeablein-situ without removal from appliance 100. For example, FIG. 6 shows anembodiment in which the portable surface cleaning unit 108 of appliance100 includes a power cable 288 for transmitting power from charging unit280 towards energy storage member 272. An advantage of a non-removableenergy storage member 272 is that it may not require a discrete outershell for user handling and transportation since it is permanently heldwithin main body 180. Further, a non-removable energy storage member 272may not require hardware to support easy user removal and insertion ofenergy storage member 272. This may reduce the size and weight ofportable surface cleaning unit 108 as compared with including charger280 within portable surface cleaning unit 108, all else being equal.

Alternatively, appliance 100 may include a power cable 288 that iselectrically connectable to a different section of appliance 100, suchas surface cleaning head 112 (See for example FIG. 18). The power cable288 can be used to transmit power from charging unit 280 to energystorage member 272 via wiring internal of appliance 100.

In some embodiments power cable 288 may be permanently connected toappliance 100. An advantage of this design is that it may not requireappliance 100 to have hardware to support a removable connection, and itmay make connecting portable appliance 100 to a stationary power supply284 more convenient to the extent that a separate power cable 288 doesnot need to be relocated to the selected power supply 284.

Alternatively, power cable 288 may be removably connected to portableappliance 100. For example, power cable 288 may be connected to portableappliance 100 only when it is desired to recharge energy storage member272. An advantage of this design is that it does not require the user tocarry the weight of power cable 288 when portable appliance 100 does notrequire a connection to a stationary power supply 284 (e.g. when notrecharging).

In an alternative configuration, appliance 100 may include the chargingunit 280 within a portion of the appliance body. An advantage of thisdesign is that it may make connecting portable appliance 100 to astationary power supply 284 more convenient, in that an external chargerdoes not need to be relocated to the selected stationary power supply284. For example, the charging unit 280 may be integrated within thebase section 104 of the appliance 100 (see for example FIG. 16).

Reference is now made to FIGS. 16-17. FIGS. 16 and 17 illustrate anexample of a portable power appliance that includes an integratedcharging unit 280. In portable power appliances, such as appliance 100,having a base unit 104 and a separate removable section 108, thecharging unit 280 may be integrated with the base unit 104. The chargingunit 280 may then recharge the energy storage members 272 in theremovable section 108, when the removable section 108 is mounted to thebase 104.

As shown, the appliance 100 may include charging unit 280 within thefloor cleaning unit 104. For example, charger 280 may be located insurface cleaning head 112 as shown, or in upper section 140. Whenportable surface cleaning unit 108 is connected to floor cleaning unit104, charger 280 may recharge energy storage member 272 (including atleast capacitor 276). In some embodiments, when charging unit 280 isconnected to a source of power, with the removable section mounted tothe base, the charging unit 280 may power the appliance 100 whilesimultaneously recharging the energy storage member 272 of the removablesection. In some embodiments, the charging unit 280 may operate torecharge the energy storage member 272 even when disconnected from apower supply, e.g. by discharging power from an onboard energy storagemember 292 as described subsequently herein.

In some embodiments, a portable power appliance 100 may include anappliance energy storage member 272 within the base section 104. Forexample, FIG. 18 illustrates an example in which an appliance energystorage member can be mounted within the surface cleaning head 112 orupper section 140 of the base 104. This appliance energy storage membercan be charged by charging unit 280 in an analogous manner to theappliance energy storage member 272 mounted within the removable section108. In some cases, the removable section 108 may also include anadditional appliance energy storage member 272 that may be chargedconcurrently with, or separately from, the appliance energy storagemember 272 mounted within the base section.

Portable Charging Unit Including Onboard Energy Storage Member

As noted above, it may be desirable for an energy storage member to becharged rapidly. It may also be desirable to provide a portable chargingunit that can charge the energy storage member, even when not connectedto a stationary power supply. This may reduce the downtime of anappliance powered by the energy storage member. This may also allow theappliance to use energy storage members with a lower power storagecapacity, or fewer total energy storage members, and reduce the overallweight of the appliance when being used with the energy storage members.

In embodiments described herein, a charging unit may be provided with anonboard energy storage member and the onboard energy storage member isused to charge an appliance energy storage member, an energy storagemember that is itself then used to power a portable power appliance,such as an ultracapacitor. The charging unit may be portable tofacilitate charging of the portable power appliance, even at locationsdistant from stationary power supplies such as mains power. For example,the charging unit could be transported on floor cleaning unit 112 or behand carriable by a user.

The features in this section may be used by itself in any appliance(e.g., surface cleaning apparatus) or in any combination orsub-combination with any other feature or features described herein.

Referring to FIGS. 5 and 7, shown therein is an example embodiment of acharging unit shown generally as 280. The charging unit 280 is asimplified example of a charging unit in which an onboard energy storagemember 292 is included as part of the charging unit 280. The chargingunit 280 is adapted to charge an appliance energy storage member, suchas energy storage member 272 used with portable appliance 100. It willbe appreciated that onboard energy storage member 292 may or may not beremovably mounted to charging unit 180 and may be fully contained in orpartially nested in charging unit 180.

The charging unit 280 generally includes a charger body 282 (which maybe referred to as a hand carriable battery charger body), chargercircuitry 284, an onboard energy storage member 292, and a power outputcircuit 290. The charging unit 280 includes a power input port 294 andat least one power output port 286 (also referred to as an applianceelectrical port).

Charger 280 may include one or more charging circuits 284 for (i)supplying power from a stationary power supply (i.e. via a power cable)to energy storage member 292, and/or (ii) supplying power from onboardenergy storage member 292 to appliance energy storage member 272, and/or(iii) supplying power from a stationary power supply (i.e. via a powercable) to appliance energy storage member 272.

As shown in the example of FIG. 7, the charging unit 280 includes acharging circuit 284 that is adapted to supply power from a stationarypower supply to onboard energy storage member 292 using power cable 296.The charging unit 280 also includes a power output circuit 290 that isadapted to supply power from onboard energy storage member 292 to anappliance energy storage member 272. In operation, the power outputcircuit 290 is adapted to electrically connect the onboard energystorage member 292 and the appliance energy storage member 272.

The charging unit 280 can be configured to operate in a number ofdifferent charging modes. In a first charging mode (also referred to asan onboard energy storage member charging mode), the charging unit 280can charge the onboard energy storage member 292 using power from astationary or mains power supply 284. The charging unit 280 can beelectrically connected to the mains power supply by power input port294. For instance, an electrical cord 296 can be used to electricallyconnect input port 294 to charging circuitry 284.

The charging circuitry 284 can be adapted to convert the power from themains power supply into a form usable to charge the onboard energystorage member 292. For instance, the mains power supply may provide ACpower, while the onboard energy storage member 292 may required DCcurrent in order to be charged. The charging circuitry 284 can thusinclude a rectifier operable to rectify the alternating current receivedfrom the mains power supply into direct current usable to charge theonboard energy storage member 292.

The charging unit 280 can also be configured to operate in a secondcharging mode, namely an appliance energy storage member charging mode(also referred to as an ultracapacitor charging mode where the applianceenergy storage member 272 includes an ultracapacitor). In the secondmode of operation, the onboard energy storage member 292 is connected topower output circuit 290. The appliance energy storage member 272 isalso connected to power output circuit 290 via power output port 286.The charging unit 280 can then charge the appliance energy storagemember 272 by discharging stored energy from the onboard energy storagemember 292 to the appliance energy storage member 272. It will beappreciated that onboard energy storage member 292 may also be rechargedwhile onboard energy storage member 292 is charging appliance energystorage member 272.

FIGS. 8A-8D illustrate various configurations of power output circuit290. As shown in FIG. 8A, the power output circuit 290 can includeonboard energy storage member 292 electrically connected to power outputport 286. The power output port 286 can include output electrodes 300 aand 300 b between which the appliance energy storage member 272 can beconnected for charging. The output electrodes 300 a and 300 b can beconnected to the respective positive and negative electrodes of theonboard energy storage member 292 (when onboard energy storage member292 is connected to the power output circuit 290).

The power output circuit 290 can also include a load component 302. Theload component may be in the form of a resistive load element or aninductive load element. When a capacitor 276 is used as the applianceenergy storage member 272, and the depleted capacitor 276 is connectedto the output port 286 (as shown in FIG. 8B), the capacitor 276 mayeffectively provide a short circuit in the output power circuit 290. Asa result, the initial inrush current through power output circuit 290may be quite high. Providing the load component 302 in series with theoutput port 286 minimizes the maximum current that is able to flowthrough the power output circuit 290, even in a short circuit condition.

In some embodiments, the appliance energy storage member 272 may beconnected to the power output circuit 290 directly. The charging unit280 may define an energy storage member receiving area 281 (as shown inFIG. 5) within which the appliance energy storage member 272 can bemounted. The power output port 286 can include an energy storage memberconnector 283 that is positioned within the energy storage memberreceiving area 281 to engage the appliance energy storage member 272when received within the energy storage member receiving area 281. Theconnector 283 can electrically connect the appliance energy storagemember 272 to the power output circuit 290. Various types of connectorsmay be used, including power connectors, USB connectors, magneticconnectors and so on.

In other cases, the appliance 100 may include an electrical cord 288that is connectable to the output port 286. The cord 288 may thenconnect the appliance energy storage member 276 to the output port 286(as shown in FIGS. 6 and 8C). The output port 286 may define anappliance power outlet to which the cord 288 can be connected.

The charging unit 280 may also be adapted to prevent overcharging ofcapacitor 276 without any overvoltage protection circuitry. Configuringthe power output circuit 280 with the output port 286 in an open circuitcharging arrangement can ensure that capacitor 276 stops charging oncethe voltage level of the onboard energy storage member 292 is reached.

The charging unit 280 may also be adapted to monitor a charge state ofthe appliance energy storage member 272. In some embodiments, thecharging unit 280 may determine the charge state of the appliance energystorage member 272 without requiring any feedback from the applianceenergy storage member 272 or appliance 100. For instance, the currentthrough power output circuit 290 may be monitored (e.g. using an ammeter304 as shown in FIG. 8D) in order to assess the charge state of thecapacitor 272.

Optionally, the charging unit may also include an output display. Theoutput display may be configured to display a charge state of theappliance energy storage member 272.

Additionally or alternatively, the output display can be configured todisplay a charge state of the onboard energy storage member 292. Thisallows a user to determine when it is necessary to connect the chargingunit 280 to mains power to recharge the onboard energy storage member292.

FIG. 9 illustrates another example of a charging unit 1280. As withcharging unit 280, the charging unit 1280 includes an onboard energystorage member 1292, charging circuitry 1284, a power output circuit1292, and an electrical input port 1294 and cord 1296. The charging unit1280 can be housed within a charging unit body similar to charging unitbody 282.

As shown in FIG. 9, the charging unit 1280 may include a power outputcircuit 1290 with multiple power output ports 1286 a and 1286 b. A firstpower output port 1286 a may be mounted within a receiving area withinwhich the appliance energy storage member 272 can be mounted directly.The second power output port 1286 b may define a power outlet to whichan electrical cord can be attached.

The power output circuit 1290 can connect either power output port 1286to an onboard energy storage member 1292 using switch 1291. In somecases, the switch 1291 may be actuated automatically in response todetecting an electrical connection at either of the output ports 1286.For instance, the power output circuit 1290 may include sensors adaptedto detect electrical connection to the output ports 1286. The sensorscan be configured to operate switch 1291 to connect the engaged poweroutput circuit 1286 to the power output circuit 1290 and onboard energystorage member 1284.

Energy storage member 292 can be any device suitable to supply power forfully recharging energy storage member 272 one or several times. Forexample, energy storage member 292 may include a battery and/or acapacitor that collectively have an energy storage capacity sufficientto recharge energy storage member 272 (or at least capacitor 276) two ormore times (e.g. three or more times, or six or more times).

In some embodiments, the charging unit 280 may be adapted to operatewith a portable power appliance such as appliance 100 in which anultracapacitor provides the appliance energy storage member. The onboardenergy storage member 292 may have sufficient power capacity to fullyrecharge the capacitor 276 of the portable power appliance 100 severaltimes. For example, the charging unit 280 may include a relativelyinexpensive, rechargeable energy storage member (e.g. a lead acid,NiCad, NiMH, or lithium) with an energy storage capacity that is severaltimes greater than the capacitor 276 of the portable power appliance100.

Alternatively, the appliance energy storage member 272 may include oneor more lithium ion batteries. The charging unit 280 may facilitaterapid recharging of the lithium ion batteries. This may allow theportable power appliance to operate using fewer batteries, reducing theoverall appliance weight.

The appliance energy storage member 272 may have sufficient energycapacity to power at least motor 212 (or all power consuming parts ofportable surface cleaning unit 108) for at least 3 minutes (e.g. 3, 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15 minutes). For example, anappliance energy storage member 272 with a capacity of at least 5 Wh canprovide 100 W of power to a suction motor 212 for at least 3 minutes. Asmentioned above, all of the energy storage may be provided by capacitor276 in some embodiments. A three-minute runtime may be plenty for shortoperational sessions, such as to clean crumbs off a couch, to clean dirtaround a planter, or to clean cereal spilled by a child for example.

Accordingly, the onboard energy storage member 292 may have a powercapacity that is several times greater than appliance energy storagemember 271 in order to fully recharge the capacitor 276 of the portablepower appliance 100 several times. For example, the onboard energystorage member 292 adapted to charge an energy storage member 272 with acapacity of at least 5 Wh may itself have a capacity of at least 20 Wh(or even greater to allow for losses during charging).

If a task is larger, and requires more runtime than energy storagemember 272 can provide, then energy storage member 272 can be quicklyrecharged. For example, charging unit 280 may be configured to rechargecapacitor 276 at a rate of at least 4 C (e.g. at least 6 C, such as 4 Cto 10 C, or 6 C to 10 C). This can allow capacitor 276 to be fullyrecharged in a matter of seconds or minutes, as compared with hours inthe case of many batteries.

In the example shown, the charging unit 280 is portable. For instance,the charging unit may weigh 1-5 pounds, 1-3 pounds.

Optionally, the charging unit 282 may include a handle on the exteriorof the charger body 282. A user may grasp the handle to lift and carrythe charging unit 280. The charging unit 280 can thus be re-positionedto facilitate charging and/or powering a portable power appliance, aswell to facilitate charging of the onboard energy storage member 292.

Additionally or alternatively, the charging unit 280 may include one ormore wheels to facilitate portability of the charging unit. Inalternative embodiments, the charging unit 280 may omit a handle and/orwheels but may nonetheless be portable. For instance, a user may carrythe charging unit 280 by grasping the exterior of the charger body 282.In some embodiments, the charging unit 280 may be integrated within thebase of a portable power appliance as described herein above.

The charging unit 280 can also include a power input port 294. The powerinput port 294 can be detachably attached to a mains power supply, forinstance by inserting the power input port 294 into a household poweroutlet 284 (e.g., it male be a male plug member). The power input port294 can subsequently be detached from the mains power supply to allowthe charging unit 280 to be re-positioned.

The power input port 294 can be coupled to the end of an electrical cord296. The electrical cord 296 may extend out from the charger body 282 toallow the charging unit 280 to be removably connected to a mains powersupply.

Optionally, the charging unit 280 may include a retractable cord reeloperable to wind and hold the cord 296. The electrical cord 296 can bemounted on the cord reel. The cord reel may be of any suitableconfiguration and may be a manually actuated reel (for example via ahand crank) or an automated reel.

If the reel is automated (i.e. can wind the cord without manual userintervention), it may be driven by any suitable mechanism including, forexample, a spring, a biasing mechanism and/or a motor. The motor usedmay be an electric motor that can be operated at a speed that issuitable for winding the cord. If the motor is electric, preferably thecord reel is provided with a power source (either on board or as part ofthe charging unit 280 such as energy storage member 292) so that thecord reel motor can be powered even after the electrical cord 296 hasbeen unplugged.

Optionally, the charging unit 280 may include a sensor adapted to sensemovement of the charging unit 280. The sensor may be operativelyconnected to the cord reel and the power cord 296 may be unwound fromthe cord reel based on movement of the charging unit 280. This mayprevent the power cord 296 from being accidentally detached from themains power supply when the charging unit 280 is moved.

In some embodiments, the charging unit 280 may be provided separatelyfrom the portable power appliance 100 (see for example FIG. 6). Forinstance, the portable power appliance 100 may operate using arechargeable energy storage member 272 that is compatible with chargingunit 280. The charging unit 280 may then be used to charge the energystorage member 272 in-situ (see for example FIG. 6) or when removed fromportable power appliance (see for example FIG. 5).

In some embodiments, the charging unit 280 and portable power appliance100 may be provided together as a kit. For instance, the charging unit280 and charger energy storage member 292 may be provided along with theportable power appliance 100 and appliance energy storage member 272ensuring compatibility between the charging unit 280 and the applianceenergy storage member 272.

Thermal Cooling Unit

The rate at which an energy storage member can be charged, withoutsuffering damage or substantial degradation, is limited by heatgenerated during charging. When an energy storage member is charged, thegenerated heat can raise the temperature of the energy storage member todangerous or damaging levels. In accordance with another aspect, thecharging unit and/or a portable appliance or an appliance includes athermal cooling unit that cools an energy storage member duringcharging. This can help keep the temperature of the energy storagemember within safe limits when the energy storage member is chargedrapidly (e.g. at a rate of 4 C or faster). Alternately, or in addition,this can help keep the temperature of the energy storage member withinsafe limits when the energy storage member is discharged rapidly (e.g.at a rate of 4 C or faster).

The features in this section may be used by itself in any appliance(e.g., surface cleaning apparatus) or in any combination orsub-combination with any other feature or features described herein.

FIGS. 11-13 illustrate various embodiments of the charging circuitry 284electrically connected to an energy storage member 272 or 292, and athermal cooling unit 308 thermally connected to one or both of theenergy storage members 272, 292 to remove heat generated duringrecharging and/or discharging, and thereby keep the temperature of theenergy storage member 272, 292 within safe limits when the energystorage member is charged or discharged rapidly. It will be appreciatedthat the arrangements described herein including a thermal cooling unit308 can be used in combination with energy storage member 272 and/or 292in any embodiment of charging unit 280 or appliance 100 describedelsewhere or illustrated in any figure.

Referring to FIG. 11, in some embodiments, thermal cooling unit 308 mayinclude active cooling. That is, thermal cooling unit 308 may include apowered cooling element 312. An advantage of this design is that therate of cooling can be controlled by regulating the power supplied tocooling element 312. This may provide better control over thetemperature of energy storage member 272, 292. Powered cooling element312 may be any powered device that can be operated to remove heat fromenergy storage member 272, 292. For example, powered cooling element 312may be a fan as shown, a coolant circulating pump, or a Peltier cooler.As shown, the charger circuitry 284 may also include cooling controlcircuitry configured to control the operation of powered cooling element312. For example, the charger circuitry 284 may control the speed of fan312 according to the temperature of energy storage member 272, 292and/or a heat sink thermally connected to or directly contacting energystorage member 272, 292.

Alternatively or in addition to a powered cooling element 312, thermalcooling unit 308 may include a passive cooling element 316. A passivecooling element 316 may be an unpowered device that is effective forremoving heat from energy storage member 272, 292 during charging. FIG.12 shows an example in which passive cooling element 316 is a heat sink(e.g. metal heat sink, such as an aluminum heat sink). FIG. 13 shows anexample in which passive cooling element 316 is a liquid heat sink. Theenergy storage member may be immersed in the cooling liquid or thecooling liquid may be in a container (housing) and the energy storagemember 272, 292 may be in thermal contact (e.g., abutting contact) withthe container.

In some embodiments, passive cooling element 316 may be configured toprovide an enlarged surface area to promote natural convective coolingwith the ambient air. For example, heat sink 316 in FIG. 12 includes aplurality of cooling fins 320 that collectively provide a large surfacearea for convective cooling of forced convection cooling. In use, energystorage member 272, 292 is positioned in contact with heat sink 316whereby heat from energy storage member 272, 292 in conducted into heatsink 316, and heat from heat sink 316 is lost by, e.g., convection intothe ambient air.

Alternatively or in addition to promoting convective heat loss, passivecooling element 316 may have a heat capacity sufficient to absorb theheat generated by one or several charges of energy storage member 272,292 and/or discharge of energy storage member 292 (e.g. at least 2charge cycles, at least 3 charge cycles, or at least 4 charge cycles).For example, passive cooling element 316 may include a volume ofmaterial that after absorbing one or several charges of energy storagemember 272, 292, maintains the energy storage member 272, 292 below atarget temperature. In FIG. 12, heat sink 316 may be composed of asufficient volume of metal (e.g. aluminum) to achieve this effect. InFIG. 13, thermal cooling unit 308 is shown including a housing 324 thatholds energy storage member 272, 292 in thermal contact with a volume ofliquid 328 (e.g. mineral oil, or other coolant). The liquid 328 may havesufficient volume to maintain the temperature of energy storage member272, 292 within safe limits after several charging cycles.

The charging unit 280 may be configured to position the thermal coolingunit 308 to contact one or both of the onboard energy storage member 292(as shown in FIG. 14) and the appliance energy storage member 272. Asshown in FIG. 14, the charging unit 280 may include a thermal coolingunit 3308 adjacent to the output port 3286 so that when appliance energystorage member 272 is inserted for charging the thermal cooling unit canabsorb heat from the appliance energy storage member 272. In someembodiments, the charging unit 280 may include a thermal cooling unit308 positioned to cool both of the appliance energy storage member 272and the onboard energy storage member 292 concurrently during charging.

Alternately, a separate thermal cooling unit may be provided for energystorage member 272 and for energy storage member 292. For example, asexemplified in FIG. 15, a thermal cooling unit 4308 is used to coolenergy storage member 4292. In the embodiment of FIG. 15, the thermalcooling unit 3308 of FIG. 14 may also be provided. It will beappreciated that the thermal cooling units may be the same or different.For example, one or both may be active or passive cooling elements.

The thermal cooling unit 308 may be integrated into the base 287 and/orsidewalls 285 of an appliance energy storage member receiving area 281.In some cases, the sidewalls 285 of the charging unit body 282 may beadapted to surround part of or to substantially surround the sides ofthe appliance energy storage member 272 when appliance energy storagemember 272 is mounted within the receiving area. Integrating the passivecooling element 316 into the sidewalls 285 may provide an increasedsurface area to promote heat exchange between the appliance energystorage member 272 and passive cooling element 316. This may enable thepassive cooling element 316 to absorb a greater proportion of the heatemitted from appliance energy storage member 272 during chargingthereof.

As noted, additionally or alternatively, the thermal cooling unit 308(such as a passive cooling element 316) may be configured to cool theonboard energy storage member 292. The onboard energy storage member 292may be mounted within the base 287 of the charging unit 280.Accordingly, positioning the thermal cooling unit 308 (such as a passivecooling element 316) within base 287 may encourage cooling of theonboard energy storage member 292.

In some cases, the thermal cooling unit 308 (such as a passive coolingelement 316) may be positioned within the base 287 between the receivingarea 281 and the onboard energy storage member 292. The thermal coolingelement 308 may thus cool both the onboard energy storage member 292 andappliance energy storage member 272 when appliance energy storage member272 is being charged.

In some embodiments, the thermal cooling unit 308 may include multiplepassive cooling elements 316 distributed throughout the charging unitbody 282. For example, a first cooling element may be provided withinthe base 287 thermally coupled at least to the onboard energy storagemember 292 while one or more secondary cooling elements are positionedwithin the sidewalls 285 to thermally contact an appliance energystorage member 272 positioned within receiving area 281.

While reference is made herein to cooling elements being positionedwithin the sidewalls 285 and/or base 287 of the charging unit body 282,it should be understood that such cooling elements may be positionedwithin those body components, integrated as part of the body 282, and/ormounted on interior or exterior surfaces of the body 282.

After passive cooling element 316 has absorbed the heat generated by oneor more charge cycles, passive cooling element 316 will passively coolback to room temperature while charging unit 280 is not in use. Once atroom temperature, passive cooling element 316 will again be capable ofabsorbing heat generated by a number of charge cycles. The passivecooling element 316 may cool between charging cycles (e.g. while theportable appliance is detached and in use) and/or when charging unit 280is unused for an extended period for instance while in storage. It willbe appreciated that active cooling may be used to reduce the time of apassive cooling element 316 to cool.

Portable Charging Unit with Simplified Overcharge Control

Allowing an energy storage member to be overcharged can result in damageand degradation, reducing the usable lifespan of the energy storagemember. Accordingly, the charging unit may be adapted to prevent theenergy storage member that is being charged from reaching an overvoltagecondition. However, active feedback components that monitor the chargestate of an energy storage member increase the size and cost of thecharging unit. Accordingly, the charging unit can be configured toprevent an overcharge state through the configuration of the poweroutput circuit thereby protecting the energy storage member whilereducing size, complexity and manufacturing costs.

The features in this section may be used by itself in any appliance(e.g., surface cleaning apparatus) or in any combination orsub-combination with any other feature or features described herein.

Referring to FIGS. 8A-8D, the charging unit 280 can include a poweroutput circuit 290 that is configured to reduce damage to an applianceenergy storage member used with charging unit 280. In particular, thepower output circuit 290 can be configured to ensure that the applianceenergy storage member is not charged above a pre-defined voltagethreshold.

FIG. 8A illustrates a simplified circuit schematic of the power outputcircuit 290 with the onboard energy storage member 292 electricallyconnected to the power output circuit 290. The power output circuit 290also has a power output port 286 with output electrodes 300 a and 300 bto which the appliance energy storage member 272 can be connected. Asshown, the power output circuit 290 also includes a load component 302in series between the onboard energy storage member 292 and the outputport 286.

FIG. 8B illustrates the power output circuit of FIG. 8A when acapacitive appliance energy storage member 276 is electrically connectedto the power output port 286. The appliance energy storage member 276 iselectrically connected to the power output circuit in an open circuitcharging configuration. As shown in FIGS. 8C and 8D, in some embodimentsthe appliance energy storage member 276 may be electrically connected tothe output port 286 by an electrical cord 288.

As shown in FIG. 8B, when the portable power appliance uses anultracapacitor as the appliance energy storage member, the power outputcircuit 290 essentially operates as if the ultracapacitor 276 is acapacitor within the circuit. As a result, when the ultracapacitor 276is depleted, the power output circuit 290 may see an effective shortcircuit through the ultracapacitor 276. When the ultracapacitor 276 ischarged, the ultracapacitor effectively acts as an open circuitpreventing further current flow. As a result, the maximum charge stateof the ultracapacitor 276 can be limited by the voltage of the onboardenergy storage member 292 that is connected to the power output circuit290. This ultracapacitor charging configuration ensures that apre-defined maximum charge state for the appliance energy storage member276 can be set based on the onboard energy storage member integratedinto charging unit 280. The charge endpoint for the appliance energystorage member 272 is thus defined without requiring any feedback fromappliance energy storage member 272 or active control components. Thatis, active control and monitoring of the charge state of the applianceenergy storage member 272 is not required to prevent overcharging of theultracapacitor 276.

This configuration may simplify the control and manufacturing of thecharging unit 280. For instance, charging unit 280 may omit any specificovervoltage protection circuitry for the appliance energy storage member272.

As noted above, when the capacitor 276 is connected to power outputcircuit 280 in a depleted state, the power output circuit 280 may beeffectively short-circuited. However, load component 302 can reduce theinitial inrush current through capacitor 276. The load component 302 maybe configured as a resistive or inductive load (e.g., a resistor) toensure that the initial inrush current is minimized. This can avoid anypotential damage to the capacitor that might otherwise occur due to highcurrents.

Optionally, the charging unit 280 may include an output display. In someembodiments, the output display can be configured to display the chargestate of the onboard energy storage member 292. Additionally oralternatively, the output display can be configured to display a chargestate of the appliance energy storage member 272 when the applianceenergy storage member 272 is electrically connected to the power outputcircuit 290.

The charging circuitry 284 may include a control circuit that isoperable to determine the charge state of one or both of the onboardenergy storage member 292 and the appliance energy storage member 272.For instance, the charge state of the onboard energy storage member 292may be determined by monitoring the voltage level of the onboard energystorage member 292.

The control circuitry may be configured to measure a current flow levelthrough power output circuit 290. For example, as shown in FIG. 8D, anammeter 304 may be positioned in the power output circuit in series withthe output port 286. The ammeter 304 can be used to measure the flow ofcurrent through the appliance energy storage member 272 when theappliance energy storage member 272 is electrically connected to theappliance electrical port 286. As the charge state of the capacitor 276increases, the resistance experienced by the power output circuit 290will increase, and the current will correspondingly decrease. Bymonitoring the current through power output circuit 290, the controlcircuitry can determine a relative charge state of the capacitor 276.This may provide a simplified charge monitoring configuration that doesnot require any communication with, or feedback from, the applianceenergy storage member 272.

Charging Unit Configured to Directly Power Appliance

In some embodiments, an appliance charging unit may be configured topower a portable power appliance directly, i.e., concurrently whilecharging the appliance energy storage member and/or the onboard energystorage member, or while not charging the appliance energy storagemember and the onboard energy storage member. This may allow thecharging unit to operate as a mobile power supply for the portable powerappliance that has greater capacity than the appliance energy storagemembers. This may provide a longer operational runtime for the portablepower appliance, even when away from a stationary power supply.

The features in this section may be used by itself in any appliance(e.g., surface cleaning apparatus) or in any combination orsub-combination with any other feature or features described herein.

In some embodiments, the charging units 280 and 1280 described hereinabove may be configured to power a portable power appliance directly, inaddition to charging an appliance energy storage member and/or anonboard energy storage member.

For example, in a first mode of operation, the charging unit 280 itselfcan be configured to power a motor 212 directly using power from theonboard energy storage member 292. This may be desirable where theportable power appliance is being used in the proximity of the chargingunit 280. This may also provide a longer operational runtime, as theonboard energy storage member 292 may have a greater storage capacitythan appliance energy storage member 272.

In some embodiments, in a second mode of operation, the charging unit280 may charge the appliance energy storage member 272 using power fromthe onboard energy storage member 292.

It will be appreciated that, in a further mode of operation, thecharging unit 280 may charge the appliance energy storage member 272while also powering the motor 212. This may occur where the dischargecapacity of the onboard energy storage member 292 is greater than thepower required to operate motor 212.

In some cases, the charging unit 280 may be preferred to operating frommains power directly, as the onboard energy storage member 292 canprovide power to the portable power appliance 100 using DC current,obviating the need for separate power conversion circuitry in theappliance 100. In some cases, when the charging unit 280 is connected tomains power, the mains power may be used to charge the onboard energystorage member 292, optionally while the onboard energy storage member292 powers the portable power appliance. When disconnected from themains power supply, the charging unit 280 can continue to power theportable appliance directly, using power stored in onboard energystorage member 292.

In some embodiments, a user may manually select between the first modeof operation and the second mode of operation. For example, a user maytoggle a switch on the portable power appliance and/or charging unit 280to select whether the first mode or operation or second mode ofoperation is engaged.

In some embodiments, the charging unit may be configured toautomatically select the first mode of operation or second mode ofoperation. For example, charging unit 1280 shown in FIG. 9 may provideseparate electrical output ports 1286 a and 1286 b for charging theappliance energy storage member 272 and for powering the appliance 100directly. The charging unit 2280 may detect which of the output ports1286 has been engaged, and select the operational mode based on theconnector that is detected.

In some embodiments, the appliance can include an appliance electricalcord. The appliance electrical cord may be separately connectable witheach of the output ports 1286 a and 1286 b. The control circuitry 1284may then select the operational mode based on the port to which the cordis connected.

In some embodiments, one of the power output ports of the charging unit280 can define a storage member power output port 1286 a. The applianceenergy storage member 272 may be directly engageable with the storagemember power output port 1286 a. When the appliance storage member 272is engaged with the storage member power output port 1286 a, thecharging unit 280 can operate in the second mode of operation to chargethe appliance storage member 272.

Reference is now made to FIGS. 10A and 10B. FIGS. 10A and 10B illustratefurther examples of charging unit 2280 that can be configured to power aportable power appliance, such as appliance 100, directly. The chargingunit 2280 are examples of charging unit in which power from a mainspower supply can be directed to the appliance 100 (or appliance energystorage member 272), when the charging unit 2280 is connected to thepower supply.

As with charging units 280 and 1280, the charging units 2280A and 2280Binclude an onboard energy storage member 2292, control and chargingcircuitry 2284, power output circuit 2290, and at least one output port2286. The charging units 2280 also include an electrical cord 2296 andpower input port 2294 that is electrically connectable to a stationarypower supply such as mains power. The charging unit 2280 can be housedwithin a charging unit body similar to charging unit body 282.

In the example shown in FIG. 10A, the charging unit 2280A includes twoseparate electrical output ports 2286 a and 2286 b. The first outputport 2286 a is usable to connect the appliance energy storage member 272to the onboard energy storage member 2292 (be it directly, using anelectrical cord, or both). When the appliance energy storage member 272is connected to output port 2286 a while in situ in portable powerappliance, the charging unit 2280 a can discharge power from the onboardenergy storage member 2292 to the portable power appliance.

In this configuration, the charging unit 2280A can be configured tooperate in multiple modes of operation. For example, in a first mode ofoperation, the charging unit 2280 can be configured to power the motor212 directly using power from the onboard energy storage member 2292.This may be desirable where the portable power appliance is being usedin the proximity of the charging unit 2280A. This may also provide alonger operational runtime, as the onboard energy storage member 2292may have a greater storage capacity than appliance energy storage member272. In some embodiments, the charging unit 2280 may also charge theappliance energy storage member 272 while powering the motor 212.

In some cases, the charging unit 2280A may be preferred to operatingfrom mains power directly, as the onboard energy storage member 2292 canprovide power to the portable power appliance 100 using DC current,obviating the need for separate power conversion circuitry in theappliance 100. In some cases, when the charging unit 2280A is connectedto mains power, the mains power may be used to charge the onboard energystorage member 2292, while the onboard energy storage member 2292 powersthe portable power appliance. When disconnected from the mains powersupply, the charging unit 2280 can be configured to power the portableappliance directly, using the power stored in onboard energy storagemember 2292.

In a second mode of operation, the charging unit 2280 can be configuredto charge the appliance energy storage member 272 using power from theonboard energy storage member 2292.

In some embodiments, a user may manually select between the first modeof operation and the second mode of operation. For example, a user maytoggle a switch on the portable power appliance and/or charging unit2280 to select whether the first mode or operation or second mode ofoperation is engaged.

In some embodiments, the charging unit 2280A may also be configured tooperate in a third mode of operation in which power from the mains powersupply is used to power the portable power appliance. For example, whenthe appliance charging unit is electrically connected to the mains powersupply, the power output circuit 2290 may be configured to direct powerfrom the mains power supply to the portable power appliance 100.

In the example shown in FIG. 10A, the charging unit 2280A includes aseparate output port 2286 b into which the portable power appliance 100can be connected to allow mains power to be directed to the portablepower appliance 100.

In some embodiments, the charging unit 2280A may provide power from thestationary power supply directly to the portable power appliance 100.However, the portable power appliance 100 may typically operate usingdirect current, while the mains supply is provided as alternatingcurrent. In some cases, the appliance 100 may incorporate powerconversion circuitry. However, this increases the size and weight ofappliance 100. Accordingly, the charging unit 2280A can be configured tooperate as a power conversion unit for appliance 100.

The charging unit 2280A can receive the mains power supply from powerinput 2294. This alternating current can then be rectified (and possiblyvoltage regulated) using control circuitry 2284 to provide the appliance100 with direct current via output port 2286 b. This allows theappliance 100 to use mains power for a longer operational runtime,without requiring additional power conversion circuitry.

FIG. 10B illustrates an alternative configuration of a charging unit2280 b that can operate in multiple operational modes. Charging unit2280 b is similar to charging unit 2280 a, except that a single outputport 2286 c is usable to power the appliance 100 using mains power orpower from the onboard energy storage member 2292.

As shown in FIG. 10B, the power output circuit 2290 a includes a switchunit 2291. The switch unit is operable to select whether the output port2286 c is connected to onboard energy storage member 2292 or to controlcircuitry 2284. In some embodiments, the switch unit 2291 may operateautomatically e.g. depending on whether charging unit 2280 b isconnected to a stationary power source. Alternatively, the charging unit2280 b may include a switch actuator that a user can manual operate toswitch between mains power and the onboard energy storage member 292.

The charging unit 2280 b can be configured to operate in a number ofdifferent operational modes. In a first mode of operation, the chargingunit 2280 can be configured to power the motor 212 directly using powerfrom the onboard energy storage member 2292. In some embodiments, thecharging unit 2280 b may be operable in this first mode of operationwhen connected to, and when disconnected from, a stationary powersupply.

In a second mode of operation, the charging unit 2280 b can beconfigured to charge the appliance energy storage member 272 using powerfrom the onboard energy storage member 2292. Again, this mode ofoperation may be engaged when charging unit 2280 b is connected to, andwhen disconnected from, a stationary power supply. In some cases,toggling between the first mode of operation and the second mode ofoperation may occur in response to a user activating or deactivating theappliance 100.

In a third mode of operation, when charging unit 2280 b is connected toa stationary power supply, the charging unit 2280 b can be configured touse power from the stationary power supply to power the appliance 100directly. As noted above, the charging circuitry 2284 may include powerconversion circuitry usable to convert the received power into DC powerusable by the appliance 100.

In a fourth mode of operation, when charging unit 2280 b is connected toa stationary power supply, the charging unit 2280 b can be configured touse power from the stationary power supply to charge the applianceenergy storage member 272. In such embodiments, the charging circuitry2284 may again include power conversion circuitry usable to convert thereceived power into DC power usable to charge the appliance energystorage member 272. In some cases, toggling between the third mode ofoperation and the fourth mode of operation may occur in response to auser activating or deactivating the appliance 100.

In some cases, the charging unit 2280 b may also charge the onboardenergy storage member 2292 concurrently while operating in the third orfourth mode of operation. The charging circuitry 2284 can be configuredto route any additional power from the stationary power supply to chargethe onboard energy storage member 2292.

Although embodiments of a charging unit and associated portable powerappliance are described herein below in the context of a portablesurface cleaning apparatus, it should be understood that various otherportable appliances may be used in the embodiments described herein.

An example of a portable power appliance having an appliance energystorage member may include an electronic cigarette that is connectableto a charging unit such as described herein above. Such as charging unitmay be electrically connected to a stationary power supply such as mainspower and/or a vehicle electrical outlet.

Further examples of portable power appliance also include various powertools such as drills, drivers, tire inflators, dremels and the like.

A battery pack usable with one or more power appliances may incorporatean appliance energy storage member as described herein above. A batterypack for electronic appliances, such as laptops or cell phones may alsobe configured as described herein above. Similarly, appliance energystorage members for children's toys, portable electronics (such asradios, testing requirement and meters), and game console controllersmay also be used.

Various kitchen appliances such as mixers, electric peelers, electricknives, rotary pot or pan scrubbers, temperature controlled containers(e.g. lunchboxes) may also be used in embodiments described herein.

Various portable culinary appliances may also be used, such as portablehot water systems, heated food containers, “Low Charcoal Use” BBQs,portable cooking ovens or stoves and the like.

Various personal portable power appliances may also be used inembodiments described herein to facilitate rapid recharging, such asflashlights, personals fans, coolers (e.g. direct or indirectevaporative coolers), space heaters, shavers, curling irons, hairdryers, sexual toys and/or aids and so on.

As used herein, the wording “and/or” is intended to represent aninclusive-or. That is, “X and/or Y” is intended to mean X or Y or both,for example. As a further example, “X, Y, and/or Z” is intended to meanX or Y or Z or any combination thereof.

While the above description describes features of example embodiments,it will be appreciated that some features and/or functions of thedescribed embodiments are susceptible to modification without departingfrom the spirit and principles of operation of the describedembodiments. For example, the various characteristics which aredescribed by means of the represented embodiments or examples may beselectively combined with each other. Accordingly, what has beendescribed above is intended to be illustrative of the claimed conceptand non-limiting. It will be understood by persons skilled in the artthat other variants and modifications may be made without departing fromthe scope of the invention as defined in the claims appended hereto. Thescope of the claims should not be limited by the preferred embodimentsand examples, but should be given the broadest interpretation consistentwith the description as a whole.

1.-33. (canceled)
 34. A charging unit for a surface cleaning apparatusthat includes a motor and an apparatus energy storage member, thecharging unit electrically connectable to a mains power supply, thecharging unit comprising: (a) a battery charger body; (b) an onboardenergy storage member; and, (c) a power output circuit electricallyconnectable to the surface cleaning apparatus; wherein when the surfacecleaning apparatus is connected to the power output circuit, thecharging unit is operable in a first mode of operation and a second modeof operation, and in the first mode of operation, the charging unit isoperable to charge the apparatus energy storage member using power fromthe onboard energy storage member, and in the second mode of operation,the charging unit is connected to the mains power supply and thecharging unit is concurrently operable to: charge the onboard energystorage member using power from the mains power supply; and charge theapparatus energy storage member using power from the onboard energystorage member.
 35. The charging unit of claim 34, wherein the chargingunit comprises a power conversion circuit operable to convert power fromthe mains power supply into a form usable to charge the onboard energystorage member.
 36. The charging unit of claim 34, wherein the poweroutput circuit omits any power conversion or power conditioningcircuitry.
 37. The charging unit of claim 34, wherein the onboard energystorage member has a positive electrode and a negative electrode andwhen the apparatus energy storage member is electrically connected tothe power output circuit, the apparatus energy storage member isconnected between the positive electrode and the negative electrode ofthe onboard energy storage member in an open circuit chargingconfiguration.
 38. The charging unit of claim 34, wherein the poweroutput circuit omits any overvoltage protection circuitry.
 39. Thecharging unit of claim 34, wherein the onboard energy storage member hasa positive electrode and a negative electrode, the power output circuitcomprises an output circuit load, and when the apparatus energy storagemember is electrically connected to the power output circuit, theapparatus energy storage member is connected in series with the outputcircuit load between the positive electrode and the negative electrode.40. The charging unit of claim 39, wherein the output circuit loadcomprises one of a load inductor and a load resistor.
 41. The chargingunit of claim 34, further comprising an output display operable todisplay a charge state of the apparatus energy storage member when theapparatus energy storage member is electrically connected to the poweroutput circuit.
 42. The charging unit of claim 41, further comprising acontrol circuit operable to determine the charge state of the apparatusenergy storage member by measuring a current flow level through thepower output circuit when the apparatus energy storage member iselectrically connected to the power output circuit.
 43. A charging unitfor a surface cleaning apparatus that includes a motor and an apparatusenergy storage member, the charging unit electrically connectable to amains power supply, the charging unit comprising: (a) a battery chargerbody; (b) an onboard energy storage member; and, (c) a power outputcircuit electrically connectable to the surface cleaning apparatus;wherein when the surface cleaning apparatus is connected to the poweroutput circuit and the charging unit is connected to the mains powersupply, the charging unit is concurrently operable to: charge theonboard energy storage member using power from the mains power supply;and charge the apparatus energy storage member using power from theonboard energy storage member.
 44. The charging unit of claim 43,wherein the charging unit comprises a power conversion circuit operableto convert power from the mains power supply into a form usable tocharge the onboard energy storage member.
 45. The charging unit of claim43, wherein the power output circuit omits any power conversion or powerconditioning circuitry.
 46. The charging unit of claim 43, wherein theonboard energy storage member has a positive electrode and a negativeelectrode and when the apparatus energy storage member is electricallyconnected to the power output circuit, the apparatus energy storagemember is connected between the positive electrode and the negativeelectrode of the onboard energy storage member in an open circuitcharging configuration.
 47. The charging unit of claim 43, wherein thepower output circuit omits any overvoltage protection circuitry.
 48. Thecharging unit of claim 43, wherein the onboard energy storage member hasa positive electrode and a negative electrode, the power output circuitcomprises an output circuit load, and when the apparatus energy storagemember is electrically connected to the power output circuit, theapparatus energy storage member is connected in series with the outputcircuit load between the positive electrode and the negative electrode.49. The charging unit of claim 48, wherein the output circuit loadcomprises one of a load inductor and a load resistor.
 50. The chargingunit of claim 43, further comprising an output display operable todisplay a charge state of the apparatus energy storage member when theapparatus energy storage member is electrically connected to the poweroutput circuit.
 51. The charging unit of claim 50, further comprising acontrol circuit operable to determine the charge state of the apparatusenergy storage member by measuring a current flow level through thepower output circuit when the apparatus energy storage member iselectrically connected to the power output circuit.